Is reprogramming a Junkyard ECM possible when you have a possibly broken IMMU (Immobi
03-05-2013, 03:36 PM
#81
once the key signals are programmed into the ecu - it will let you use those keys
try to reset the codes again and check what happens when you are trying to start the car - if the security light stays solid or not (I know you stated it worked, but this should be done to see what triggers the code)
there is no difference if you got two different key on one ring - if system detects the proper key - ECU will command the NATS unit to let the car start
fuel pump will be heard before start up even if you have the wrong coded key - it just pump in the gas as you turn the key into "ON" position, when the key is not recognized - it will be blocked as well as spark on some of the vehicles
to insure that ECU is still good, you could open it up and check for the burnt chips
side question - if car is causing this many issues, why not part it out - make money back - get a different one
i'm not sure how much you have spent on it, but sounds like you will have to invest more just to fix IACV P0505 code, which might be caused by 1 of 6-7 components and do a relearn after that (ran 85 dollars for me)
i'm not saying you have to give up - but it's a good project, you are just standing on the same spot, asking same questions
03-05-2013, 10:28 PM
#82
Junior Member
Thread Starter
Join Date: May 2009
Posts: 62
.........EUREKA!!!!.........
I GOT IT TO START!
ARE YOU READY FOR THIS? THE CULPRIT!!
Thats right. A simple blown fuse, but a very important fuse apparently.
Under Hood: ENG CONT 1 (Engine Control 1)
I GOT IT TO START!
ARE YOU READY FOR THIS? THE CULPRIT!!
Thats right. A simple blown fuse, but a very important fuse apparently.
Under Hood: ENG CONT 1 (Engine Control 1)
As soon as I replaced the blown fuse with one of the spares, the car started right up ON THE 1ST TRY!!! I later realized that had I replaced the fuse before replacing the ECU and then reprogramming the keys to the new old junkyard ECU, that I would've kept blowing fuses or caused other damage to the car. So, this was the moment to replace this fuse.
Curiously, there are NO CODES. ZERO. After clearing the codes and putting the fuse back in, the P505 went away as well as the P1615. WEIRD or MAKES SENSE?
This car hadn't run since August 28th, 2012, the date of Hurricane Isaac. Tonight it ran fine for 25 minutes.... until......
.... a slight little snafu arose. Apparently fast release of the gas pedal causes the car to stall. Smooth and slow increase and decrease of the throttle allows the car to keep running. This is the problem I believe existed prior to 8/28/2012 that was causing the car to stall occasionally.
When I turned on the a/c, the RPMs slightly went down and didn't go back up. I'm pretty sure turning on the A/C is supposed to raise RPMs slightly to about 900rpm to compensate for the load. That about right?
So what would cause the car to stall at idle/park after sharply releasing the throttle pedal from about 1500-2000 rpms??
Curiously, there are NO CODES. ZERO. After clearing the codes and putting the fuse back in, the P505 went away as well as the P1615. WEIRD or MAKES SENSE?
This car hadn't run since August 28th, 2012, the date of Hurricane Isaac. Tonight it ran fine for 25 minutes.... until......
.... a slight little snafu arose. Apparently fast release of the gas pedal causes the car to stall. Smooth and slow increase and decrease of the throttle allows the car to keep running. This is the problem I believe existed prior to 8/28/2012 that was causing the car to stall occasionally.
When I turned on the a/c, the RPMs slightly went down and didn't go back up. I'm pretty sure turning on the A/C is supposed to raise RPMs slightly to about 900rpm to compensate for the load. That about right?
So what would cause the car to stall at idle/park after sharply releasing the throttle pedal from about 1500-2000 rpms??
03-05-2013, 10:58 PM
#83
This is great news!! Your perseverance has paid off. Congrats!
You may have a problem with the IACV, though. While it may not be shorted to cause the P0505 code, the resistance of the coils inside the IACV may be bad. In the FSM see page 432 in the EC section for the schematic and page 436 for the resistance check.
The idle speed should be about the same when the a/c is on. On my car when I turn the a/c on, the idle dips for a fraction of a second and then goes back up to 650, its normal idle speed.
But maybe the throttle body needs to be cleaned.
You may have a problem with the IACV, though. While it may not be shorted to cause the P0505 code, the resistance of the coils inside the IACV may be bad. In the FSM see page 432 in the EC section for the schematic and page 436 for the resistance check.
The idle speed should be about the same when the a/c is on. On my car when I turn the a/c on, the idle dips for a fraction of a second and then goes back up to 650, its normal idle speed.
But maybe the throttle body needs to be cleaned.
03-06-2013, 09:57 AM
#84
Junior Member
Thread Starter
Join Date: May 2009
Posts: 62
This is great news!! Your perseverance has paid off. Congrats!
You may have a problem with the IACV, though. While it may not be shorted to cause the P0505 code, the resistance of the coils inside the IACV may be bad. In the FSM see page 432 in the EC section for the schematic and page 436 for the resistance check.
The idle speed should be about the same when the a/c is on. On my car when I turn the a/c on, the idle dips for a fraction of a second and then goes back up to 650, its normal idle speed.
But maybe the throttle body needs to be cleaned.
You may have a problem with the IACV, though. While it may not be shorted to cause the P0505 code, the resistance of the coils inside the IACV may be bad. In the FSM see page 432 in the EC section for the schematic and page 436 for the resistance check.
The idle speed should be about the same when the a/c is on. On my car when I turn the a/c on, the idle dips for a fraction of a second and then goes back up to 650, its normal idle speed.
But maybe the throttle body needs to be cleaned.
I will check the IAC resistance. I've had to do this before on other cars too. I was thinking about just replacing the IAC and TPS altogether to make sure I don't blow the new old junkyard ECU.
I'm also considering unplugging the motor mount sensors or actuators... whatever they are.. because I've heard/read that when the mounts go bad it can fry your ECU. Anyone care to comment on that?
Throttle body was supposed to have been cleaned already by a trusted shop about 8 months ago, though you never know how well they actually did it.
What is the correct method for cleaning the throttle body on this car?
Lastly, I heard there is an idle relearn procedure after replacing the IAC. Is there a sticky for that in this forum or somewhere else, that is a reliable guide to do this?
03-07-2013, 12:54 AM
#85
good to see you have finally figured it out!
on our years (2000-2001) electronic mounts can cause IACV and ECU to burn. Even Dave B (very trusted and knowledgeable dealer employee) told me to disconnect them, so I would recommend you yo do the same
try to put some new gas in there and check the spark plugs, those might cause problems with those hiccups and stalls
Once you take off the accordion on the throttle body - you will see if it was cleaned up. Autozone and other retailers are offering Throttle body cleaner by CNC. You can open the valve and check if there is any dirt on the inside too.
While cleaning try to avoid getting cleaner into IACV ports. Also there is the procedure somewhere on the forums with pics.
Don't touch TPS - usually it doesn't go bad and is an expensive piece to replace. If you want - you could put fuses onto IACV wiring to avoid burning the ECU, someone also described that on here.
For me procedure with relearn at home wasn't that successful, I did it at the shop with Launch computer (Snap On and Mac tools sell those for a big buck).
Try checking how loose the cables for throttle and cruise are, also check resistance before putting fuses in as per DennisMik's post and ECM
on our years (2000-2001) electronic mounts can cause IACV and ECU to burn. Even Dave B (very trusted and knowledgeable dealer employee) told me to disconnect them, so I would recommend you yo do the same
try to put some new gas in there and check the spark plugs, those might cause problems with those hiccups and stalls
Once you take off the accordion on the throttle body - you will see if it was cleaned up. Autozone and other retailers are offering Throttle body cleaner by CNC. You can open the valve and check if there is any dirt on the inside too.
While cleaning try to avoid getting cleaner into IACV ports. Also there is the procedure somewhere on the forums with pics.
Don't touch TPS - usually it doesn't go bad and is an expensive piece to replace. If you want - you could put fuses onto IACV wiring to avoid burning the ECU, someone also described that on here.
For me procedure with relearn at home wasn't that successful, I did it at the shop with Launch computer (Snap On and Mac tools sell those for a big buck).
Try checking how loose the cables for throttle and cruise are, also check resistance before putting fuses in as per DennisMik's post and ECM
03-07-2013, 09:32 PM
#86
Engine Control 1 fuse powers the IACV internal stepper motor and the ignition coils. Nothing important. 
725 rpm is in the idle range for an auto trans car. My car is about 750, not 650. I like to have brain farts and confuse people.
Electric motor mounts could cause the STA509 chips in the ECU to burn up. If this were to happen, you would not get a check engine light and you would probably never know it ever happened. The electric motor mount gets softer at idle and stiffens up at rpms over 1K. It does this by pumping oil into a rubber bladder to stiffen it or pumping the oil out. So it is really a hydraulic motor mount, not an electric motor mount. And whoever started describing it as an electronic motor mount was wayyyy off. But it sounded fancy and caught on.
The way shaks worded it, it sounds like a bad motor mount could burn up the IACV. If you got that impression like me, it's not true.
If the possibility of the motor mount shorting out the ECU chips bothers you, you can unplug them. But do it while the engine is over 1K rpm so that the mounts will be in the firm mode. The only negative to doing this is that you may feel more engine vibrations at idle.
The motor mount is self contained. It has an electric motor, an oil reservoir and a pump. But maybe I shouldn't call the pump a pump. The reservoir is like a box with a movable side. The motor turns a screw and makes the reservoir bigger or smaller. When the screw reaches its limit, the motor is supposed to turn itself off. If something happens to this shut-off mechanism - POOF goes the ECU chip.
Here's some pics of a dissected motor mount.
http://forums.maxima.org/album.php?albumid=6654
pic 1 - the mount.
pic 3 - electric motor on the bottom.
pic 4 - electric motor removed, revealing pump screw.
pic 5 - electric motor pump drive tang.
pics 6 & 7 - electric motor opened up.
pic 9 - oil reservoir inside the bladder, oil passage is visible.
725 rpm is in the idle range for an auto trans car. My car is about 750, not 650. I like to have brain farts and confuse people.
Electric motor mounts could cause the STA509 chips in the ECU to burn up. If this were to happen, you would not get a check engine light and you would probably never know it ever happened. The electric motor mount gets softer at idle and stiffens up at rpms over 1K. It does this by pumping oil into a rubber bladder to stiffen it or pumping the oil out. So it is really a hydraulic motor mount, not an electric motor mount. And whoever started describing it as an electronic motor mount was wayyyy off. But it sounded fancy and caught on.
The way shaks worded it, it sounds like a bad motor mount could burn up the IACV. If you got that impression like me, it's not true.
If the possibility of the motor mount shorting out the ECU chips bothers you, you can unplug them. But do it while the engine is over 1K rpm so that the mounts will be in the firm mode. The only negative to doing this is that you may feel more engine vibrations at idle.
The motor mount is self contained. It has an electric motor, an oil reservoir and a pump. But maybe I shouldn't call the pump a pump. The reservoir is like a box with a movable side. The motor turns a screw and makes the reservoir bigger or smaller. When the screw reaches its limit, the motor is supposed to turn itself off. If something happens to this shut-off mechanism - POOF goes the ECU chip.
Here's some pics of a dissected motor mount.
http://forums.maxima.org/album.php?albumid=6654
pic 1 - the mount.
pic 3 - electric motor on the bottom.
pic 4 - electric motor removed, revealing pump screw.
pic 5 - electric motor pump drive tang.
pics 6 & 7 - electric motor opened up.
pic 9 - oil reservoir inside the bladder, oil passage is visible.
10-04-2023, 05:29 AM
#87
Newbie - Just Registered
Join Date: Oct 2023
Posts: 1
Update
2001 Maxima 3.0L engine with no traction control and cali spec
I have been posting here (http://x.nissanhelp.com/forums/maxim...html#post86805) getting great help, but I would like to see if anyone here can help even more so since this is a primarily Maxima forum.
This is for my mom's car who doesn't have money for a new one and is disabled for walking too well, but she can drive and its the last freedom she has. So I'm trying to save the car for her as it has only 65k miles on it.
I have purchased a ECM/ECU from a Junkyard (good looking shape). Prior to installing it my Mom was having problems starting it and if she could start it it would only kick on a second or 2 and then stall out. IAC and Fuel pump was ruled out. After replacing both, the car still would not start sometimes. I am suspecting the Immobilizer unit (IMMU, because no third party shop could figure it out.
I have the car sitting dead at Nissan right now and I had to replace the ECM (because of damage to the old one) and I brought it there so they could reprogram the keys to the junkyard (used, but new to me) ECM. They are using the Consult II tool and they enter the code to get into the system, but it doesn't allow them in and there are no errors or anything showing up in their screen... it just doesn't allow them in to reprogram the keys against the replacement JUNKYARD ECM.
1. I have learned that if the IMMU was bad, it wouldn't allow them to get to the ECM. Is that how ya'll understand it as well?
2. Is it possible for Nissan to reprogram the keys to an already differently VIN'ed ECM if I purchase and install a new IMMU?
I am trying to avoid big costs obviously and they are wanting to put in a brand new Nissan ECM. Though I am considering letting Nissan order a new IMMU and new ECM to see if we can't get the car started again.
Advice? Thoughts? I really want to know if ya'll think the dealer doesn't know what they are doing... because to me this should be possible, but if the IMMU is blocking the reprogramming to the ECM I was hoping there would be some way to tell the IMMU is faulty before going through all this.
Thanks ahead of time. Your help may help save my senior citizen parents from having to owe on another car for the rest of their lives.
I have been posting here (http://x.nissanhelp.com/forums/maxim...html#post86805) getting great help, but I would like to see if anyone here can help even more so since this is a primarily Maxima forum.
This is for my mom's car who doesn't have money for a new one and is disabled for walking too well, but she can drive and its the last freedom she has. So I'm trying to save the car for her as it has only 65k miles on it.
I have purchased a ECM/ECU from a Junkyard (good looking shape). Prior to installing it my Mom was having problems starting it and if she could start it it would only kick on a second or 2 and then stall out. IAC and Fuel pump was ruled out. After replacing both, the car still would not start sometimes. I am suspecting the Immobilizer unit (IMMU, because no third party shop could figure it out.
I have the car sitting dead at Nissan right now and I had to replace the ECM (because of damage to the old one) and I brought it there so they could reprogram the keys to the junkyard (used, but new to me) ECM. They are using the Consult II tool and they enter the code to get into the system, but it doesn't allow them in and there are no errors or anything showing up in their screen... it just doesn't allow them in to reprogram the keys against the replacement JUNKYARD ECM.
1. I have learned that if the IMMU was bad, it wouldn't allow them to get to the ECM. Is that how ya'll understand it as well?
2. Is it possible for Nissan to reprogram the keys to an already differently VIN'ed ECM if I purchase and install a new IMMU?
I am trying to avoid big costs obviously and they are wanting to put in a brand new Nissan ECM. Though I am considering letting Nissan order a new IMMU and new ECM to see if we can't get the car started again.
Advice? Thoughts? I really want to know if ya'll think the dealer doesn't know what they are doing... because to me this should be possible, but if the IMMU is blocking the reprogramming to the ECM I was hoping there would be some way to tell the IMMU is faulty before going through all this.
Thanks ahead of time. Your help may help save my senior citizen parents from having to owe on another car for the rest of their lives.
A friend mechanic tried a boost and said my battery is at 11.5 should be higher. Also he had a scanner and it wouldn’t read codes. Nissan said new ecm needed can’t read codes. Okay. But I have been reading a lot about this and it tells me something had to wrong for the ecm to quit in the first place.
If I pay a lot of money for the ecm they will then see what’s wrong! I think that’s quite unfair. It’s Nissan use a test board and then tell me why it died and then we can talk. That was my opinion. Anyone got any ideas the cheapest way I can go about doing this? The dealerships at Nissan are charging way too much for nothing!! Imo
Last edited by Ripoff; 10-04-2023 at 05:46 AM.
10-04-2023, 10:41 AM
#88
Did this ever get repaired? I have my 2014 Murano in for repairs now. Very disgusted with Nissan right now. The suv quit mid driving at 80kms an hour. Miracle it didn’t cause an accident. No driving ability. Every light on the dash came on and wouldn’t go off. Even when we took a cable off the battery and put it back on the vehicle would bring back all the lights. Tried the key fob in the ignition. Still no go. Brake lights worked. Even the ac and the phone connected to the vehicle when making a phone call. Weird considering it disconnects when you shut off the vehicle for the last 10yrs. So that tells me somewhere this vehicle is registering the ignition on.
A friend mechanic tried a boost and said my battery is at 11.5 should be higher. Also he had a scanner and it wouldn’t read codes. Nissan said new ecm needed can’t read codes. Okay. But I have been reading a lot about this and it tells me something had to wrong for the ecm to quit in the first place.
If I pay a lot of money for the ecm they will then see what’s wrong! I think that’s quite unfair. It’s Nissan use a test board and then tell me why it died and then we can talk. That was my opinion. Anyone got any ideas the cheapest way I can go about doing this? The dealerships at Nissan are charging way too much for nothing!! Imo
A friend mechanic tried a boost and said my battery is at 11.5 should be higher. Also he had a scanner and it wouldn’t read codes. Nissan said new ecm needed can’t read codes. Okay. But I have been reading a lot about this and it tells me something had to wrong for the ecm to quit in the first place.
If I pay a lot of money for the ecm they will then see what’s wrong! I think that’s quite unfair. It’s Nissan use a test board and then tell me why it died and then we can talk. That was my opinion. Anyone got any ideas the cheapest way I can go about doing this? The dealerships at Nissan are charging way too much for nothing!! Imo
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